March 2018 Summary – Second Snowiest on Record
Blue Hill Observatory
March 2018 Summary:
The first half of March was exceptionally stormy with three significant Nor’easters bringing about eight inches of precipitation and about 40 inches of snow within twelve days, and the month was generally cooler than average. The 24-hour adjusted mean temperature for the month of 33.9 deg F was 0.5 degrees cooler than the 120-year average for March and 1.8 degrees cooler than the 1981-2010 30-year average. For the second consecutive year and for only the fifth time since 1885 at the Observatory, March was colder than February. Much of the cold was due to low day-time temperatures, since the average maximum temperature for March was about 3 deg F cooler than average, while the average minimum temperature was just over 1 deg F warmer than average. The warmest temperature for the month was 62F on the 30th, and the coldest temperature was 10F on the 18th. A total of 8.68 inches of precipitation was measured during the month, which was about four inches more than the long-term 120-year average and about three inches more than the 30-year mean, and the month was the eighth wettest March on record. About eight inches of the total was measured during a series of three powerful storms on the 2nd, 7th-8th, and the 13th. The greatest in 24 hours was 3.47 inches during a rain storm on the 2nd that brought very strong winds including a peak gust to 73 mph at the Observatory, heavy snow well inland, and severe coastal flooding. The second major storm brought 2.16 inches of precipitation, 15.0 inches of snow, and a wind gust to 52 mph. The third major storm was all snow bringing a total of 23.0 inches of snowfall in less than 24 hours on the 13th and 2.20 inches of liquid equivalent with a peak wind gust to 60 mph. This storm tied for the fourth largest March snowstorm ever observed at Blue Hill, and the snowfall was the largest amount ever measured in March on a single calendar day. Snowfall for March totaled 45.5 inches, which was almost four times more than the 30-year average, making this the second snowiest March on record behind only 52.0 inches in 1956. The mean wind speed for the month was 14.3 mph, and the prevailing direction was from the northwest. A peak gust of 73 mph from the north-northeast occurred during the rain storm on the 2nd. March was much cloudier than average with 145.7 hours of bright sunshine, or 41 percent of the possible, which was eight percent less than the long-term mean.
BHO Lowest Mar-Feb 24-hour Mean Temperature Difference, deg F (1885-2018):
1) -5.4 in 1984
2) -3.1 in 1960
3) -2.2 in 2017
-2.2 in 2018
5) -0.3 in 1937
6) +0.8 in 1890
+0.8 in 1997
8) +0.9 in 1939
9) +1.2 in 1954
BHO March Highest Monthly Precipitation, inches (1885-2018):
1) 18.81 in 2010
2) 13.07 in 2001
3) 10.96 in 1968
4) 10.02 in 1983
5) 9.53 in 1953
6) 9.00 in 1984
7) 8.72 in 1993
8) 8.68 in 2018
9) 8.09 in 1956
10) 7.98 in 1994
BHO March Highest Monthly Snowfall, inches (1885-2018):
1) 52.0 in 1956
2) 45.5 in 2018
3) 42.2 in 1916
4) 41.4 in 2001
5) 41.0 in 1967
6) 37.8 in 2013
7) 35.5 in 1993
BHO Greatest March Snowstorms, inches (1885-2018):
1) 30.3 on 3-5 Mar, 1960
2) 30.0 on 31 Mar – 1 Apr, 1997
3) 29.8 on 6-8 Mar, 2013
4) 23.0 on 5-7 Mar, 2001
23.0 on 13 Mar, 2018
6) 19.5 on 19-20 Mar, 1956
7) 17.8 on 15-16 Mar, 1967
8) 17.5 on 20-22 Mar, 1958
9) 16.9 on 11-14 Mar, 1939
10) 15.4 on 29-30 Mar, 1984
BHO Greatest Snowstorms, inches (1885-2018):
1) 38.7 on 24-28 Feb 1969
2) 30.8 on 26-28 Jan 2015
3) 30.3 on 3-5 Mar 1960
4) 30.1 on 6-7 Feb 1978
5) 30.0 on 31 Mar – 1 Apr 1997
6) 29.8 on 6-8 Mar 2013
7) 26.6 on 8-9 Feb 2013
8) 24.7 on 17-18 Feb 2003
9) 24.3 on 5-7 Dec 2003
10) 23.0 on 5-7 Mar, 2001
23.0 on 13 Mar, 2018
BHO Greatest March Calendar Day Snowfalls, inches (1885-2018):
1) 23.0 on 13 Mar, 2018
2) 18.0 on 8 Mar, 2013
3) 17.6 on 19 Mar, 1956
4) 17.3 on 4 Mar, 1960
5) 15.5 on 6 Mar, 2001
6) 15.0 on 31 Mar, 1997
7) 13.5 on 29 Mar, 1984
8) 13.0 on 5 Mar, 1891
9) 12.8 on 3 Mar, 1960
10) 12.3 on 24 Mar, 1956
Mike Iacono
Chief Scientist
Blue Hill Observatory
